Line laser emitting device and high-precision elevation measurement method

Abstract

The invention discloses a line laser emitting device and a high-precision elevation measurement method. The line laser emitting device comprises a shell, and a rotary driving mechanism, an optical conversion module and a laser source which are mounted in the shell, the optical conversion module comprises a prism bracket, a cubic beam splitter prism, a Powell prism, a driving gear II, a driven gear II and a motor II; the rotation driving mechanism drives the prism bracket to rotate; an opening is formed in the bottom of the prism bracket, a clamping groove located over the opening is formed in the middle of the prism bracket, a bearing is arranged on one side of the prism bracket, the driven gear II is embedded in the left end of the Powell prism, the right end of the Powell prism is installed in the bearing, and the cubic beam splitter prism is fixed in the clamping groove; and the driving gear II is mounted on an output shaft of the motor II and is meshed with the driven gear II. According to the invention, high-precision measurement can be realized with lower cost, and meanwhile, the data acquisition frequency and precision are improved, so that the availability and efficiency of equipment are improved, especially in a high-frequency vibration working environment.

Description

Technical Field

[0001] The invention relates to a line laser emitting device and a high-precision elevation measurement method, belonging to the technical field of intelligent construction of roadbed and pavement. Background Art

[0002] In the current field of measurement technology, laser measurement equipment is widely used due to its high precision and fast response. Especially with the assistance of the Global Positioning System (GPS) and other satellite navigation systems, laser measurement technology has become a key tool in the field of intelligent construction of transportation and civil engineering.

[0003] However, despite the significant progress in accuracy and reliability of existing laser measurement equipment, there are still some limitations. The first is the performance in high-frequency vibration working scenarios. Laser measurement equipment is usually subject to high-frequency vibration noise from rollers during road construction operations, with a vibration frequency of around 50Hz. During measurement, increasing the data acquisition frequency and setting anti-vibration measures for the hardware can effectively improve data accuracy. Increasing the rotation frequency of the rotating laser can effectively increase the amount of data per unit time. The increase in rotation frequency will test the stability and power consumption of the device. The published invention patent (publication number: CN117630998A) mentions an improved laser signal receiving device, which uses a layered array arrangement of laser sensors. Although it can increase the data sampling frequency, it increases the production cost exponentially. Existing high-precision laser measurement equipment is often expensive, and the data error caused by high-frequency vibration is not considered, which limits their application in resource-limited environments or small-scale projects. Summary of the invention

[0004] In order to solve the technical problems existing in the prior art, the present invention provides a line laser emitting device and a high-precision elevation measurement method; the present invention can achieve high-precision measurement at a lower cost, while improving the data acquisition frequency and accuracy, thereby improving the availability and efficiency of the equipment, especially in a high-frequency vibration working environment.

[0005] The technical solution provided by the present invention to solve the above technical problems is: a line laser emitting device, comprising a housing and a rotating drive mechanism installed in the housing, an optical conversion module, and a laser source; The optical conversion module comprises a prism bracket, a cubic beam splitter prism, a Powell prism, a driving gear II, a driven gear II, and a motor II; the prism bracket is fixed on the rotary drive mechanism, and the prism bracket is driven to rotate by the rotary drive mechanism; the prism bracket is provided with an opening at the bottom, a clamping groove located directly above the opening in the middle, and a bearing on one side; the driven gear II is nested at the left end of the Powell prism, the right end of the Powell prism is installed in the bearing, and the cubic beam splitter prism is fixed in the clamping groove; the driving gear II is installed on the output shaft of the motor II and meshes with the driven gear II; The shell is provided with a notch facing the Powell prism; the laser source is located directly below the cubic beam splitter prism.

[0006] A further technical solution is that the rotary drive mechanism includes a driving gear I, a driven gear I, a motor I, and a vertical shaft; the driven gear I is rotatably mounted on the vertical shaft, the driving gear I is mounted on the output shaft of the motor I, and meshes with the driven gear I; the prism bracket is fixed on the driven gear I, and a through hole is axially provided on the vertical shaft directly below the opening, and the laser source is located directly below the through hole.

[0007] A further technical solution is that the prism bracket is fixed to the driven gear I by bolts.

[0008] A further technical solution is that the prism bracket is made of aluminum alloy.

[0009] A further technical solution is that the shell is made of ABS engineering plastic material.

[0010] A further technical solution is that a high-transmittance quartz glass is arranged in the notch to protect the Powell prism from the influence of the external environment.

[0011] A high-precision height measurement method specifically comprises the following steps: Step 1: Place the line laser emitting device at the reference point, and after centering and leveling, start the line laser emitting device. The line laser emitting device emits a rotating line laser in space, and the line laser deflects in space at the same time; Step 2: Place the line laser receiving device at the point to be measured, and adjust its receiving laser direction to face the line laser emitting device; Step 3, record the corresponding data of the linear laser during the acquisition time, and substitute it into the elevation calculation formula to calculate the final value of the relative elevation between the center of the linear laser receiving device and the center of the linear laser emitting device; Step 4: Calculate the absolute elevation of the center of the line laser receiving device based on the final value of the relative elevation.

[0012] A further technical solution is that the specific process of the deflection of the line laser in space in step 1 is: the driving gear II is driven by the motor II, and the driven gear II and the Powell prism are driven to rotate. First, the driving gear II rotates clockwise. α degrees, and then rotate the driving gear II counterclockwise 2 α degrees, and finally rotate the driving gear Ⅱ clockwise α Degree reset, where α The range is 15°~35°.

[0013] A further technical solution is that the elevation calculation formula includes:

[0014]

[0015] Where: Δ H is the final value of the relative elevation between the center of the line laser receiving device and the center of the line laser emitting device; Δ H i For the i The calculated relative elevation value between the center of the line laser receiving device and the center of the line laser emitting device calculated for the second time; n is the number of calculated values, the size is ; p is the proportion of data to be excluded, and its value range is 0~0.5; p × n Excludes both ends of the data set p × n The floor value of the observation; h 0 is the vertical distance between the upper sensor and the lower sensor in the line laser receiving device, a is the vertical spacing correction coefficient, ranging from 0.5 to 1.5. ω is the rotation speed of the line laser emitting device, f 1 is the sine function in trigonometric function, f 2 is the tangent function in trigonometric function, t i1 , t i2 , t i3 They are the time data of three responses of the upper sensor of the linear laser receiving device arranged from small to large. t j1 , t j2 , t j3 They are respectively the time data of three responses of the lower sensor of the linear laser receiving device arranged from small to large.

[0016] A further technical solution is that the calculation formula in step 4 is:

[0017] Where: H A is the absolute height of the center of the line laser receiving device, H B is the absolute height of the center of the line laser emitting device, Δ H It is the final value of the relative elevation between the center of the line laser receiving device and the center of the line laser emitting device.

[0018] The beneficial effects of the present invention are: 1. The structure of the laser emission end is optimized, especially the beam splitter prism component. Only one beam splitter prism and one Powell prism component are used. The angle of the Powell prism is adjusted by the rotating mechanism to realize the rotation of line lasers of different shapes in space; 2. A high-precision distance measurement algorithm is proposed. The laser rotates 10 times in 1 second to obtain 10 data. Three of the data are substituted into the calculation formula to obtain an elevation calculation value. Take 3 out of 10, that is, =120, and the data update frequency is 120Hz. In road construction, the frequency of vibration compaction of the roller is about 50Hz, 120>50, that is, the algorithm can effectively avoid the influence of vibration noise of the roller. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the overall structure of a linear laser emitting device of the present invention; Figure 2 is a schematic diagram of a Powell prism conversion line laser of the present invention; Figure 3 It is a schematic diagram of the deflection range of the line laser; Figure 4 It is a schematic diagram of a line laser emitting device emitting a line laser; Figure 5 It is a schematic diagram of the installation of a line laser emitting device and a line laser receiving device in the high-precision elevation measurement method of the present invention.

[0020] As shown in the figure: 1-housing; 2-laser source; 3-through hole; 4-vertical axis; 5-driven gear I; 6-Powell prism; 7-driven gear II; 8-driving gear II; 9-motor II; 10-cube beam splitter; 11-prism bracket; 12-high-transmittance quartz glass; 13-opening; 14-driving gear I; 15-through hole. DETAILED DESCRIPTION

[0021] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0023] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0025] like Figure 1 As shown, a line laser emitting device provided by the present invention comprises a housing 1 and a rotation drive mechanism, an optical conversion module, and a laser source 2 installed in the housing 1; The laser source 2 emits point-shaped laser from bottom to top, the laser wavelength is 635nm, the laser power is 2mW, the laser source works in a continuous wave mode, and is fixed to the inner wall of the housing 1; The optical conversion module comprises a prism bracket 11 (made of aluminum alloy), a cubic beam splitter prism 10, a Powell prism 6, a driving gear II 8, a driven gear II 7, and a motor II 9; the prism bracket 11 is fixed on the rotary drive mechanism, and the prism bracket 11 is driven by the rotary drive mechanism to rotate clockwise at a speed of 600 rpm (600 revolutions per minute, 10 revolutions per second); the bottom of the prism bracket 11 is provided with an opening 13 with a diameter of 20 mm, the middle is provided with a positioning groove (size of 20 mm long and 20 mm wide) located directly above the opening 13, and the side wall has A bearing hole with a diameter of 25 mm, in which a bearing (with an inner diameter of 20 mm and an outer diameter of 25 mm, used to bear radial loads and achieve precise rotational motion) is horizontally arranged, the cubic beam splitter prism 10 is fixed in the positioning groove by UV glue, the driven gear II7 is nested in the left end of the Powell prism 6, and the right end of the Powell prism 6 is horizontally installed in the bearing, and its right end extends into the prism bracket 11 and faces the left side of the cubic beam splitter prism 10; the driving gear II8 is installed on the output shaft of the motor II9 and meshes with the driven gear II7; The cubic beam splitter prism 10 is used to change the propagation path of the point laser, converting the point laser propagating from bottom to top into horizontal propagation, with a size of 20mm×20mm×20mm, an operating wavelength range of 400~700nm, and a splitting ratio of 70R / 30T; the transmission ratio of the driven gear II7 to the driving gear II8 is 1; The Powell prism 6 is used to convert the point laser into a line laser (such as Figure 2 As shown), the diameter is 20mm and the divergence angle is 30°; The housing 1 is provided with a notch facing the Powell prism 6 ; the laser source 2 is located directly below the cubic beam splitter prism 10 .

[0026] The motor II9 drives the driven gear II7 through the driving gear II8, and deflects according to the deflection rule, thereby realizing the deflection of the line laser in space. The rotation speed of the driving gear II8 is 50 rpm. Initially, the angle between the line laser and the plumb line is 0°. The deflection rule is that the driving gear II8 rotates clockwise first. α degrees, and then rotate the driving gear Ⅱ8 counterclockwise 2 α degrees, and finally rotate the driving gear Ⅱ8 clockwise α Degree reset, α The range is 15°~35°; (e.g. Figure 3 shown) In this embodiment, a specific implementation of the rotation drive mechanism is to include a driving gear I14, a driven gear I5, a motor I15, and a vertical shaft 4, which are used to drive the prism bracket 11 to rotate clockwise at a rotation speed of 600 rpm (600 revolutions per minute, 10 revolutions per second); the driven gear I is rotatably mounted on the vertical shaft, the driving gear I is mounted on the output shaft of the motor I, and meshes with the driven gear I; the prism bracket 11 is fixed to the driven gear I5 by bolts, and the vertical shaft 4 is axially provided with a through hole 3 located directly below the opening 13, and the laser source is located directly below the through hole 3; in this way, the point laser emitted from the laser source 2 from bottom to top passes through the through hole 3 and the opening 13 in sequence, and enters the cubic beam splitter prism 10, and then passes through the cubic beam splitter prism 10 to enter the Powell prism 6, and the Powell prism 6 converts the point laser into a line laser and emits it out of the housing 1 (such as Figure 4 as shown).

[0027] In this embodiment, the shell 1, which is used to encapsulate and protect internal electronic components, is made of ABS engineering plastic material. The shell 1 has the characteristics of impact resistance, insulation and wear resistance, and is formed by an injection molding process, and its wall thickness is uniform to ensure mechanical strength and stability.

[0028] In this embodiment, in order to protect the Powell prism 6, a preferred implementation is that a high-transmittance quartz glass 12 is provided at the notch on the upper side of the housing 1 to protect the Powell prism 6 from the influence of the external environment, such as dust, moisture, solvents and mechanical damage.

[0029] like Figure 5 As shown, a high-precision height measurement method using the above embodiment specifically includes the following steps: Step 1: Place the line laser emitting device at the reference point, and after centering and leveling, start the line laser emitting device. The line laser emitting device emits a rotating line laser in space, and the line laser deflects in space according to the deflection rule; The deflection rule is: the rotation speed of the driving gear II8 is 50 rpm. Initially, the angle between the line laser and the plumb line is 0°. The deflection rule is that the driving gear II82 is first rotated clockwise by α degrees, and then the driving gear II8 is rotated counterclockwise by 2 degrees. α degrees, and finally rotate the driving gear Ⅱ8 clockwise α Degree reset, α The range is 15°~35°; Step 2: Place the line laser receiving device at the point to be measured, and adjust its receiving laser direction to face the line laser emitting device; Step 3, record the corresponding data of the line laser within the acquisition time t, and substitute it into the elevation calculation formula to calculate the final value of the relative elevation between the center of the line laser receiving device and the center of the line laser emitting device; Within the acquisition time t, the line laser receiving device has 10×t response data to the line laser emitted by the line laser emitting device. Three of the response data are randomly selected and substituted into the elevation calculation formula for calculation. The total is There are 100 kinds of methods, times (subsequently replaced by n), the final relative elevation value between the center of the line laser receiving device and the center of the line laser emitting device is calculated using the truncated mean algorithm (reducing the influence of extreme values ​​on the overall mean value), and the calculation method is as follows:

[0030]

[0031] Where: Δ H is the final value of the relative elevation between the center of the line laser receiving device and the center of the line laser emitting device; Δ H i For the i The calculated relative elevation value between the center of the line laser receiving device and the center of the line laser emitting device calculated for the second time; n is the number of calculated values, the size is ; p is the proportion of data to be excluded, and its value range is 0~0.5; p × n Excludes both ends of the data set p × n The floor value of the observation; h 0 is the vertical distance between the upper sensor and the lower sensor in the line laser receiving device, a is the vertical spacing correction coefficient, ranging from 0.5 to 1.5. ω is the rotation speed of the line laser emitting device, f 1 is the sine function in trigonometric function, f 2 is the tangent function in trigonometric function, t i1 , t i2 , t i3 They are the time data of three responses of the upper sensor of the linear laser receiving device arranged from small to large. t j1 , t j2 , t j3 They are respectively the time data of three responses of the lower sensor of the line laser receiving device arranged from small to large; Step 4, calculating the absolute elevation of the center of the line laser receiving device according to the final value of the relative elevation;

[0032] Where: H A is the absolute height of the center of the line laser receiving device, H B is the absolute height of the center of the line laser emitting device, Δ H It is the final value of the relative elevation between the center of the line laser receiving device and the center of the line laser emitting device.

[0033] The above description is not intended to impose any form of limitation on the present invention. Although the present invention has been disclosed through the above embodiments, it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of the technical solution of the present invention.

Claims

1. A line laser emitting device, It is characterized in that It includes a housing and a rotating drive mechanism, an optical conversion module, and a laser source installed in the housing; The optical conversion module comprises a prism bracket, a cubic beam splitter prism, a Powell prism, a driving gear II, a driven gear II, and a motor II; the prism bracket is fixed on the rotary drive mechanism, and the prism bracket is driven to rotate by the rotary drive mechanism; the prism bracket is provided with an opening at the bottom, a clamping groove located directly above the opening in the middle, and a bearing on one side; the driven gear II is nested at the left end of the Powell prism, the right end of the Powell prism is installed in the bearing, and the cubic beam splitter prism is fixed in the clamping groove; the driving gear II is installed on the output shaft of the motor II and meshes with the driven gear II; The shell is provided with a notch facing the Powell prism; the laser source is located directly below the cubic beam splitter prism.

2. A line laser emitting device according to claim 1, It is characterized in that The rotary drive mechanism includes a driving gear I, a driven gear I, a motor I, and a vertical shaft; the driven gear I is rotatably mounted on the vertical shaft, the driving gear I is mounted on the output shaft of the motor I, and is meshed with the driven gear I; the prism bracket is fixed on the driven gear I, a through hole is axially provided on the vertical shaft and is located directly below the opening, and the laser source is located directly below the through hole.

3. A line laser emitting device according to claim 2, It is characterized in that The prism bracket is fixed on the driven gear I by bolts.

4. A line laser emitting device according to claim 1, It is characterized in that The prism bracket is made of aluminum alloy.

5. A line laser emitting device according to claim 1, It is characterized in that The shell is made of ABS engineering plastic material.

6. A line laser emitting device according to claim 1, It is characterized in that High-transmittance quartz glass is arranged in the notch to protect the Powell prism from the influence of the external environment.

7. A high-precision elevation measurement method, It is characterized in that The method uses a line laser emitting device as described in any one of claims 1 to 6 for measurement, and specifically comprises the following steps: Step 1: Place the line laser emitting device at the reference point, and after centering and leveling, start the line laser emitting device. The line laser emitting device emits a rotating line laser in space, and the line laser deflects in space at the same time; Step 2: Place the line laser receiving device at the point to be measured, and adjust its receiving laser direction to face the line laser emitting device; Step 3, record the corresponding data of the linear laser during the acquisition time, and substitute it into the elevation calculation formula to calculate the final value of the relative elevation between the center of the linear laser receiving device and the center of the linear laser emitting device; Step 4: Calculate the absolute elevation of the center of the line laser receiving device based on the final value of the relative elevation.

8. A high-precision height measurement method according to claim 7, It is characterized in that The specific process of the deflection of the line laser in space in step 1 is as follows: the driving gear II is driven by the motor II, and the driven gear II and the Powell prism are driven to rotate. First, the driving gear II rotates clockwise. α degrees, and then rotate the driving gear II counterclockwise by 2 α degrees, and finally rotate the driving gear Ⅱ clockwise α Degree reset, where α The range is 15°~35°.

9. A high-precision height measurement method according to claim 7, It is characterized in that The elevation calculation formula includes: Where: Δ H is the final value of the relative elevation between the center of the line laser receiving device and the center of the line laser emitting device; Δ H i For the i The calculated relative elevation value between the center of the line laser receiving device and the center of the line laser emitting device calculated for the second time; n is the number of calculated values, the size is ; p is the proportion of data to be excluded, and its value range is 0~0.5; p × n Excludes both ends of the data set p × n The floor value of the observation; h 0 is the vertical distance between the upper sensor and the lower sensor in the line laser receiving device, a is the vertical spacing correction coefficient, ranging from 0.5 to 1.

5. ω is the rotation speed of the line laser emitting device, f 1 is the sine function in trigonometric function, f 2 is the tangent function in trigonometric function, t i1 , t i2 , t i3 They are the time data of three responses of the upper sensor of the linear laser receiving device arranged from small to large. t j1 , t j2 , t j3 They are respectively the time data of three responses of the lower sensor of the linear laser receiving device arranged from small to large.

10. A high-precision height measurement method according to claim 7, It is characterized in that The calculation formula in step 4 is: Where: H A is the absolute height of the center of the line laser receiving device, H B is the absolute height of the center of the line laser emitting device, Δ H It is the final value of the relative elevation between the center of the line laser receiving device and the center of the line laser emitting device.

Images